3ii Dominican Fossils — Maury 147 



aperture .50, greatest diameter .75 mm. 



Locality. — (Exp'd '16) Bluff 3, Cercado de Mao. 



Genus Turbonilla Risso 



Turbonilla (Chemnitzia) OgilviecE, n. sp. 



Plate 25, Figure 11 



Shell very slender and delicate, whorls twelve to thirteen in 

 addition to the small helicoid protoconch, volutions nearly fiat 

 to slightly rounded, ornamented with heavy, nearly straight ribs, 

 slightly curved near the upper suture, and ending very abruptly 

 at the periphery of the body whorl number of ribs on the last three 

 whorls seventeen each; interspaces smooth and polished; suture 

 distinct, bordered posteriorly by a smooth, narrowband; base of 

 shell smooth; columellar fold inconspicuous. Length 6.5, diam- 

 eter 1 mm. 



This little shell belongs to the subgenus Chemnitzia d'Or- 

 bigny. It is named in honor of Professor Ida H. Ogilvie of Bar- 

 nard College. 



Gabb's unfigured T. augusta appears to have been a Chem- 

 nitzia but is invalid, as Carpenter had used the name nine years 

 before. 



Locality. — (Exp'd '16) Bluff 3, Cercado de Mao. 



Turbonilla (Chemnitzia) yaquensis, n. sp. 

 Plate 25, Figure 12 



Shell very small and slender, with ten slightly convex 

 whorls ornamented with narrow oblique ribs which extend to the 

 posterior suture and end abruptly at the periphery of the last 

 whorl; interspaces considerably wider than the ribs, smooth and 

 porcellanous; the last three whorls each have about thirteen ribs; 

 suture distinct; columellar fold inconspicuous. Length 3.60, di- 

 ameter .65 mm. 



This shell is distinguished by its small size, slightly convex 

 whorls, and oblique ribs, much narrower than their interspaces. 



